Thought Process

From Problem 435 I already made a fibonacci mod function, which I copied for this problem.

To find a(n) I use my Miller Primality Test, which is guaranteed to find primes, I simply try every number after n and see if it is a prime. I originally made the miller test for Problem 291 but didn't end up using, so glad it was useful!

But as it turned out once I got the correct answer, I tried using my Fermat Primality Test with 5 tests and it ended up being correct and faster...

I have added both my Fermat Primality test and Miller Primality test to my essential functions page and it is already implemented in my math module